【作者】 李素琼；

【导师】 黄彪；

【作者基本信息】 福建农林大学 ， 林产化学加工工程， 2011， 硕士

【摘要】 本文以杉木屑为原料,分别采用机械力化学磷酸法、氯化锌法和助活化剂(磷酸-硝酸钾)法制备了高吸附性能的活性炭。依据响应面法原理,使用Design-Expert软件的筛选重要因子设计(Plackett-Burman Design) (PBD)模式和中心组合设计(Box-Behnken Design) (BBD)模式、中心复合设计(Central Composite Design) (CCD)模式和建立试验数学模型,对机械力化学法制备活性炭的有关影响因素进行试验优化设计,并进行试验验证分析,探讨了影响机械力化学法活性炭孔隙结构和碘吸附值、亚甲基蓝吸附值等各种制备因素,确定了制备活性炭的最佳工艺条件。对于机械力化学技术磷酸法制备活性炭,对碘吸附值模型的预测值与试验真实值之间的相关性为98.66%,该模型能够解释97.31%的响应值变化,说明模型拟合程度良好；得出的最佳制备工艺参数为：酸屑比2.00,研磨时间22.00 min,活化温度406.00℃,磷酸浓度20.00%,活性炭的碘吸附值达到1331.23mg/g。对于亚甲基蓝模型的决定系数为0.9910,调整系数为0.9820,最佳制备工艺条件为：酸屑比2.60,研磨时间29.00 min,活化温度390.00℃,磷酸浓度22.50%,制得的活性炭样品的亚甲基蓝吸附值为21.50ml/0.1g。机械力化学技术氯化锌法制备活性炭,碘吸附值模型的预测值与试验真实值之间的相关性为99.38%,该模型解释了98.79%的响应值变化,表明该模型有良好的拟合程度；最佳制备工艺条件为：锌屑比2.70,研磨时间34.00min,活化温度593.00℃,活化时间1.90 h,活性炭的碘吸附值为1189.23mg/g。对于亚甲基蓝模型的决定系数为0.9927,调整系数为0.9858,最佳制备工艺条件是：锌屑比1.80,研磨时间22.00 min,活化温度672.00℃,活化时间1.22 h,活性炭的亚甲基蓝吸附值为24.30ml/0.1g。机械力化学技术助活化剂(磷酸-硝酸钾)法制备活性炭,碘吸附值模型的预测值与试验真实值之间的相关性达97.99%,该模型能解释96.12%响应值的变化,说明模型拟合较好；酸屑比为2.60,助剂用量为14.00%,研磨时间为19.00min,磷酸浓度为15.00%,活化温度400.00℃,活化时间60.00 min时,活性炭的碘吸附值达到1007.86mg/g。亚甲基蓝吸附值模型的预测值与试验真实值之间的相关性为98.65%,该模型解释了97.40%的响应值变化,该模型有良好的拟合程度；在酸屑比为2.60,助剂用量为9.00%,研磨时间为40.00min,磷酸浓度为23.00%,活化温度400.00℃,活化时间60.00min时时活性炭的亚甲基蓝吸附值为23.00ml/0.1g。通过对三种活性炭制备方法最优条件下碘值和亚甲基蓝的吸附值的对比发现,采用机械力化学技术磷酸法制备活性炭时,活性炭的碘吸附值最大,为1331.23mg/g；机械力化学技术助活化剂(磷酸-硝酸钾)法制备活性炭时,活性炭的亚甲基蓝吸附值最大,为24.30ml/0.1g。另一方面,对上述制备的活性炭用比表面积及孔隙分析仪、扫描电子显微镜(SEM)、傅立叶红外光谱仪(FT-IR)等作进一步表征,为机械力化学法制备高性能活性炭提供了理论依据。更多还原

【Abstract】 In this thesis,we developed novel activated carbon with high performance by introducing mechanochemical process (MCP) into traditional ways for activated carbon preparation include phosphoric acid activation, zinc chloride activation and phosphoric acid-potassium nitrate activation. Plackett-Burman design (PBD), Box-Behnken design (BBD) and central composite design (CCD) were applied using Desgn-Expert software to optimize the conditions of preparation according RSM.Fitting of the data to various models (linear, two factorial, quadratic and cubic) and their subsequent ANOVA showed that iodine adsorption for MCP/phosphoric acid preparation was most suitably described with a quadratic polynomial model. A suitable coefficient of determination (R2= 0.9866) and similar adjusted R2 (adj-R2=0.9731) also showed that the quadratic polynomial model was highly significant and sufficient to represent the actual relationship between the response and the significant variables. Results showed that highest iodine adsorption (1331.23 mg/g) could be got under the following conditions:ratio of acid/sawdust 2.00, milling time 22.00 min, activation temperature 406.00℃, and concentration of phosphoric acid 20%. The same analysis also been done for methylene blue adsorption. A suitable coefficient of determination (R2= 0.9910) and similar adjusted R2 (adj-R2=0.9820) showed a good fit of the quadratic polynomial models with experimental data. Results showed that highest methylene blue adsorption (21.50 ml/0.1g) could be got under the following conditions:ratio of acid/sawdust 2.60, milling time 29.00 min, activation temperature 390.00℃, and concentration of phosphoric acid 22.5%.We also used the same analysis to work out the best mathematic model for MCP/zinc chloride preparation and MCP/phosphoric acid-potassium nitrate activation. These results also indicated that quadratic polynomial models sufficient to represent the actual relationship between the response and the significant variables. The optimum conditions of iodine adsorption for both activations were (1) ratio of zinc chloride/sawdust 2.7, milling time 34.00 min, activation temperature 593.00℃, activation time 1.90 h; and (2) ratio off activation reagent/sawdust 2.6, dosage of activation regent 14.00%, milling time 19.00 min, concentration of phosphoric acid 15.00%, activation temperature 400.00℃, activation time 60 min respectively. For methylene blue adsorption, the optimum conditions were (1) ratio of zinc chloride/sawdust 1.8, milling time 22.00 min, activation temperature 672.00℃, activation time 1.22 h; and (2) ratio off activation reagent/sawdust 2.6, dosage of activation regent 9.00%, milling time 40.00 min, concentration of phosphoric acid 23.00%, activation temperature 400.00℃, activation time 60 min respectively for MCP/zinc chloride preparation and MCP/phosphoric acid-potassium nitrate activation. Compare with MCP/zinc chloride preparation and MCP/phosphoric acid-potassium nitrate activation, MCP/phosphoric acid preparation showed highest iodine adsorption; and the MCP/zinc chloride preparation showed highest methylene blue adsorption.Furthermore, the activated carbons regenerated under the optimum condition for MCP/phosphoric acid preparation, MCP/zinc chloride preparation, and MCP/phosphoric acid-p otassium nitrate activation preparation were characterized by BET, SEM and FTIR.更多还原